PROFESSIONAL ETHICS

It is clear from these data that direct microscopy of faeces for Giardia is well worth while, and is considerably better than the 20~~ suggested by Dr McMillan. Detection of cysts of Giardia by direct microscopy obviates the need to perform the more time-consuming concentration tests. We have found that the presence of mucus in addition to meat fibres on microscopy is common in faecal specimens from patients with giardiasis and believe this finding should prompt a careful search for these parasites. Institute of Medical and Veterinary Science, T. W. STEELE, Box 14 Rundle Street P.O., Adelaide, S.A. 5000. S. McDERMOTT.

t is clear from these data that direct microscopy of faeces for Giardia is well worth while, and is considerably better than the 20~s uggested by Dr McMillan. Detection of cysts of Giardia by direct microscopy obviates the need to perform the more time-consuming concentration tests. We have found that the presence of mucus in addition to meat fibres on microscopy is common in faecal specimens from patients with giardiasis and believe this finding should prompt a careful search for these parasites. Institute

SEXUAL SIDE EFFECTS OF DRUGS
SIR: In recent years, the scientific literature has noted the sexual side effects of many drugs. This evaluation has mainly consisted of clinical observations. While valuable in indicating the necessity for further investigations, there have been few adequately controlled double-blind studies carried out to confirm these opinions. In many reports, interpretation is limited by the inadequate descriptions of changes in sexual behaviour. For example, "impotence" has been used to denote male sexual disorders from premature ejaculation to erectile failure. "Loss of libido" has covered such widely varying conditions as vaginismus and absence of pleasurable feelings during coitus. The methodological problems involved in measuring sexual behaviour changes in humans may well have hindered investigations. Techniques of assessing sexual behaviour include interview, psychological and physiological measurements. I There is an added problem in evaluating any effects of psychotropic drugs, as disturbed sexual behaviour may be a concomitant part of the psychiatric illness which necessitates use of such drugs.
Perhaps these methodological difficulties partly explain the curiosity in the published literature, whereby reported side effects relate mainly to male sexual performance, and effects on female sexual functioning have been largely ignored. Is female sexual behaviour little affected by the antihypertensives, antidepressants and antipsychotics implicated in male sexual dysfunction? Does the lack of reported female sexual side effects reflect the failure of women to voluntarily report such side effects, or the disinterest or discomfort of a male-dominated profession' It is of interest that most attention to side effects of drugs in female sexual behaviour has focused on an exclusively female-orientated preparation, the oral contraceptive pill.
Drugs may affect sexual behaviour by their central or peripheral effects. Everett presents evidence to suggest that dopamine is the primal mobilizing neurohormone for sexual behaviour, and that serotonin is a major inhibitor.? Dopamine receptor blockers (such as haloperidol and phenothiazines), and depletors of dopamine (such as reserpine) would be expected to interfere with the central control of sexual behaviour.
Peripheral effects of drugs on male sexual behaviour were reviewed by Bell. 3 He suggests that penile erection is mediated mainly by the parasympathetic nervous system. whereas ejaculation and orgasm are a function of the sympathetic system. Bell found that drugs which caused ejaculatory failure interfered with sympathetic functioning. These included the alpha-adrenoreceptor blockers, phenoxybenzamine, the adrenergic neurone-blocking agents, guanethidine and reserpine, as well as ganglion-blocking agents. Their use may result in retrograde ejaculation, or absence of emission and orgasm. The highest incidence of reported side effects was related to guanethidine, and there was some indication that this effect may persist long after therapy because of a selective depletion of noradrenaline stores in the internal genitalia. Reports of impotence with such drugs may reflect central effects. Ganglion-blocking drugs affected both ejaculation and erection, reflecting their effect on both divisions of the autonomic nervous system. Muscarinicblocking drugs such as the tricyclics, and the monoamine oxidase inhibitors also interfere with penile erection. The mechanism of action of clonidine in causing impotence has been suggested to possibly reflect weak atropinic effects of the drug.
There is some evidence from a questionnaire study," that general depressant type drugs such as barbiturates, methaqualone, heroin and large amounts of alcohol decrease sexual activity. Large doses of amphetamines also had this effect, whereas smaller doses of alcohol or amphetamines or the use of cocaine and marihuana were said to produce the aphrodisiac effects of increasing libido and enjoyment of sex, and lowering inhibitions.
The oral contraceptive pill has been variously reported as causing sexual side effects in from 0 up to 100~~of subjects. 5 These varying reports may reflect the differing types of studies. The well controlled and planned prospective studies such as that of Cullberg" found a low incidence (from 0 to 5 0 0 ) , which may reflect a pharmacological effect of the oral contraceptive pill. Higher incidences reported in retrospective studies may have been due to the additional measurement of the "psychological" or symbolic effects of taking the Pill.
In conclusion, there is a great need for further careful evaluation of the way in which drugs affect sexual beh~viour.

PROFESSIONAL ETHICS
SIR: I wish to express my concern at the frequency with which I am confronted in the consulting room by patients whom I am already treating and who indicate that a doctor of their acquaintance has told them that certain lines of treatment should be followed, or that they should be referred to a particular specialist, or that certain investigations should be done. From the wording of the patient's remarks it is evident that the friendly doctor is aware that the patient is already receiving treatment for the condition in question.
Usually, the medical acquaintances have been met at church, or golf, or some social occasion, and the patients are confident enough to name the doctors concerned. Rarely are they general practitioners, who exercise considerable discretion in giving casual opinions, but many are specialists, or else the fringe dwellers in medicine, those who have no continuing responsibility for patients. The fact is that frequently the originator of the advice or opinion, though perhaps well meaning. is ignorant of the patient's full medical background, and of the medical attendant's plan of management and treatment.
Whether ignorant or not of the true state of affairs, the comments which these people make are damaging both to the doctor-patient relationship, the practitioner looking after the patient, and often to the originator of the comments as well. If the practitioner, in order to keep the peace, accedes to the suggestions made through the patient, he appears to that patient as a little less than competent. If, with sound reasons, he refutes the suggestions, then the originator of the comments appears to the patient as incompetent or ill informed. DECEMBER 24/31, 1977 The ethics of our profession surely demand that these off-the-cuff opinions, advice and criticisms relating to another practitioner's handling of a case should cease. If the individuals involved are genuinely concerned about a situation, they should contact the doctor in question. If they are merely chattering, as I believe is often the case, or are perhaps seeking admiration by airing their expert knowledge, then it is time that they became mindful of the possible damage that might be caused, and should guard their tongues more closely. One gives them the benefit of the doubt in thinking that, generally, these individuals are thoughtless and not vindictive.

METHYLDOPA AND RENAL STONES
SIR: I noted Dr Ramsay's retrospective study' with interest. I agree with him that methyldopa appears to be an uncommon cause of kidney stones. I described the possible association in two patients," but these were the only ones to whom it appeared to apply in nearly 300 patients with recurring and bilateral stones. However, if, as Dr Ramsay stated, methyldopa could be the primary cause of stone formation in, at most, four patients out of 16 with bilateral calculi, this would give an incidence of 25%, which would be higher than the prevalence of primary hyperparathyroidism in most series of patients with bilateral stones.
I pointed to the insolubility of methyldopa (one part in 100 parts of water), and suggested that it may deposit in the urine and act as a nidus for stone formation. I used the term "nidus" in the sense employed by Hamburger's group when they state "it is possible that calculi may be induced by certain formations that play the part of a nucleus of crystallization".' Dr Ramsay offers, as an alternative explanation, the possibility that the drug could precipitate in the urine and worsen the tendency to stone formation. This seems to be very similar to the concept of acting as a nidus.
Finally, it appears important to be able to prevent stone formation whenever possible. Therefore, if a new cause of stone is found, it appears reasonable to act on this, even if it is a rare event. The first of my patients ceased therapy with methyldopa in October, 1972, andthe second in February, 1974. Neither patient has formed any new stones since she ceased to take the drug.
, Ramsay, L. E., MED. J. AUST., 1977,2: 495. 2 Murphy, K. J., MED. J. AUST., 1976,2: 20. 3 Hamburger, J., Richet, G., Crosnier, J., et alii, Nephrology, Saunders, Philadelphia, 1968, 2: 1124 RISK OF RABIES TO OVERSEAS TRAVELLERS SIR: As rabies is fortunately not endemic in Australia and New Zealand, it tends to be forgotten when those who intend to go overseas seck advice about the medical hazards of travel. The disease is present in most overseas countries. Intending travellers should be warned not to play with, fondle, pat or otherwise fraternize with animals in such countries. The offering of food is fraught with risk. Several people have reported being bitten on the hand by monkeys in Bali, to whom they were feeding peanuts. This is a regular tourist attraction there, but the traveller should be advised to avoid the animals. As these are feral creatures which return to the jungle, it is impossible to know whether a particular animal is rabid or not. Furthermore, monkeys infected with rabies virus have been reported from India, Indonesia, Ethiopia, Zambia, Argentina, Peru and Venezuela.' While the risk of a particular monkey being infective is probably low, figures for the attack rate amongst monkeys in Bali are not currently available, but are being sought.
As many readers will know, rabies has spread from Poland and Germany across the Continent amongst wild animals, mainly foxes, and has now reached the Channel. Transmission of the rabies virus from feral to domesticated animals has occurred in these countries, where the dog constitutes the greatest risk to man. Rabies is not endemic at the moment in the United Kingdom, although the risk exists that animals incubating rabies could be smuggled into the United Kingdom from Europe, The traveller who sustains a bite, scratch, or even is licked by an animal, should wash the site, immediately with soap if available, or with a detergent (for example, hair shampoo), which is likely to contain a quaternary ammonium compound (such as cetrimide), and seek medical advice without delay. Many travellers who have returned from overseas report that they have been bitten by an animal several weeks previously. Protection is most effective if immediate local treatment of the wound is given, including a local injection of rabies antiserum (preferably rabies immunoglobulin of human origin), plus an appropriate course of immunization started as soon as possible after the bite.
The HEALTH RISKS OF URANIUM SIR: Your editorial by Charles Kerr is most informative, and summarizes for the layman much of the current knowledge about health risks from the use of uranium.' An ". .. 'extremely serious accident' applied to a hypothetical population often million people " may lead " ... to a casualty list of 3300 acute radiation fatalities ". This amount approximates the expected number of road deaths throughout Australia each year. The 45 000 fatal cancers to be expected are about the same as the number of lung cancer deaths from cigarette smoking in Australia in the last eight to 10 years. The possibility of a nuclear accident causing these deaths is extremely small, indeed almost infinitesimal. The road toll and lung cancer figures are absolutely certain. In his last paragraph, Charles Kerr states in summary that considerable actual and potential hazards surround the nuclear power industry and that many imponderables remain with much greater efforts being required to find safe solutions to waste disposal. Once these are found, he says, " ... the public has to be convinced that the solutions are indeed safe".
To dignify the public with a corporate intelligence is completely misleading, because the public, like the law, is an ass. It ignores entirely the fact that the rest of the world is busily going ahead with uranium development and that nothing Australia may do will change this. It views with equanimity the vast number of preventable deaths that occur in our society each year, but apparently under appropriate Marxist stimulation becomes extremely excited at the very remote prospect of a uranium disaster. It is probable that uranium has not caused the loss of a single life in the last 20 years of commercial development. In the extremely unlikely event of a nuclear disaster ever occurring in Australia, it would account for no more than one year's death toll on Australian roads and eight to 10 years' deaths from lung cancer caused by voluntary ciagerette smoking. There can surely be no doubt of the public's insincerity, stupidity, and complete absence of balance when applied to the subject of uranium mining, development and disposal.
A NEW ANTIDEPRESSANT BUTRIPTYLINE SIR: We read with interest the paper on butriptyline by Burrows et alii. ' We were surprised by the certainty of their claim that "The results of this study confirm previous findings that butriptyline is an effective antidepressant. ..". Changes in scores are always difficult to interpret, and the moderate response in some of their patients may have been due to other factors than the drug administered, for example, patient expectations (placebo effect), experimenter bias, regression effects or spontaneous improvement in time. Patient 2 appeared to be